1. Field of the Invention
There is a continuing interest in the upgrading of fuels, particularly coal, to provide fuels having a wide variety of applications and coming within specified standards, such as environmental standards, physical standards, and the like. Because of the relatively large supplies of coal, much attention has been focused on the use of coal to replace oil. Bituminous and subbituminous coal has only limited utility as obtained from mining operation. The coal contains substantial amounts of sulfur, nitrogen and inorganic compounds such as calcium salts. In order to meet environmental standards, it is necessary to remove substantial amounts of the sulfur and nitrogen. Since calcium and other inorganics have no fuel value, they act to reduce the heat content per unit weight of coal and are contaminants which must be removed from a combustion zone. Furthermore they may interfere with the proper operation of the fuel combustion apparatus. In addition, in many generation operations it is desirous to have a liquid, rather than a solid fuel.
In any refining of coal to upgrade the coal to an acceptable fuel, it is essential that the system be economical and efficient and, whenever possible, provide at least a portion of the fuels necessary for the processing In addition, it is desirable to produce products which have high economic value in comparison to the original coal value.
2. Description of the Prior Art
U.S. Pat. No. 3,888,896 describes a liquid phase methanol synthesis process. U.S. Pat. Nos. 3,816,322 and 3,764,547, and patents cited therein, describe a partial oxidation gasifier.